Oedometric Testing in the Laboratoires des Ponts et Chaussées, France

The Laboratoires des Ponts et Chaussées (LPC) of France are about to publish six new standards on oedometric testing. Two of these tests (controlled gradient test and controlled rate of strain test) are similar to those used in other countries. The other four have been under development at the LPC and other French research centers for the past 15 years, and exhibit special features which distinguish them from traditional standards used abroad. Briefly, the unique features are that: the incremental test was adapted for better accuracy and easier computerization of its data; the radial drainage test is very similar to the standard test; the creep test was simplified to run for less time; and the heat accelerated test was developed in France to obtain the compressibility curve of the soil in less than a week. The paper deals with the main characteristics of the testing process, the material developed in France, and interpretation techniques.